Ultra low voltage, low power active-RC filter in 90 nm CMOS technology

In this work, an ultra low voltage, second order low pass active-RC filter is designed in 90 nm CMOS process. A bulk-driven transconductor and a feed-forward compensated operational transconductance amplifier (OTA) are used as building blocks of the filter. Operating with a supply voltage of 0.5 V, filter exhibits a low pass Butterworth response with a cutoff frequency of 1 MHz. A mathematical model of the filter is developed using descriptor state-space equations for optimizing the filter response. The designed filter consumes a power as less as 91.99 μW with a figure of merit (FoM) of 3.39 fJ/pole.